1. Field of the Invention
The present invention relates to a unisometric reflection display for forgery prevention with special optical effects which is used for identification cards, passports, bills, etc., and more particularly relates to a unisometric reflection display which has fine reflectors inclined at a particular angle and an information holder in which that display is stacked on a print layer.
2. Description of the Related Art
It is desired that items, such as securities, certificates, brand-name goods, electronic devices, and personal identification media are difficult to be forged. To this end, such items may be provided with a display with excellent effects for preventing forgery.
Many of such displays include fine structures, such as a diffraction grating and a hologram, and have an effect to change in color in accordance with, for example, an angle at which they are observed. These displays with fine structures are difficult to be analyzed and forged. Therefore, they can demonstrate outstanding advantages for forgery prevention.
Moreover, these displays are used while bonded on a print layer on which identification information for items is printed, and therefore they have a feature of allowing visible light to go through them. The displays with such transparency are manufactured by applying a transparent high-refraction material along a jagged part of a fine structure.
For example, Jpn. Pat. Appln. KOKAI Publication No. 2011-221054 describes a transparent hologram in which zinc sulfide, which is a transparent high-refraction material, is dry-coated on an uneven pattern surface by a diffraction grating. Japanese Patent No. 4868090 describes a transparent hologram with a more complicated structure of layers.
Furthermore, Patent Jpn. Pat. Appln. KOKAI Publication No. 5-212344 official report discloses a technique to print a powdered magnetic material oriented by magnetic lines of force, and Patent Jpn. PCT National Publication No. 2011-521090 discloses a scale pigment which uses a carbonyl iron powder which can be oriented with magnetism as a base material.